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// Copyright (c) 2010 ARM Limited
// All rights reserved
//
// The license below extends only to copyright in the software and shall
// not be construed as granting a license to any other intellectual
// property including but not limited to intellectual property relating
// to a hardware implementation of the functionality of the software
// licensed hereunder.  You may use the software subject to the license
// terms below provided that you ensure that this notice is replicated
// unmodified and in its entirety in all distributions of the software,
// modified or unmodified, in source code or in binary form.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met: redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer;
// redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution;
// neither the name of the copyright holders nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Authors: Gabe Black

def format ArmDataProcReg() {{
    instDecode = '''
          case %(opcode)#x:
            if (immShift) {
                if (setCc) {
                    return new %(className)sRegCc(machInst, %(dest)s, %(op1)s,
                                                   rm, imm5, type);
                } else {
                    return new %(className)sReg(machInst, %(dest)s, %(op1)s,
                                                 rm, imm5, type);
                }
            } else {
                if (setCc) {
                    return new %(className)sRegRegCc(machInst, %(dest)s,
                                                      %(op1)s, rm, rs, type);
                } else {
                    return new %(className)sRegReg(machInst, %(dest)s,
                                                    %(op1)s, rm, rs, type);
                }
            }
            break;
    '''

    def instCode(opcode, mnem, dest="rd", op1="rn"):
        global instDecode
        return instDecode % { "className": mnem.capitalize(),
                              "opcode": opcode,
                              "dest": dest,
                              "op1": op1 }

    decode_block = '''
    {
        const bool immShift = (bits(machInst, 4) == 0);
        const bool setCc = (bits(machInst, 20) == 1);
        const uint32_t imm5 = bits(machInst, 11, 7);
        const ArmShiftType type = (ArmShiftType)(uint32_t)bits(machInst, 6, 5);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)RD;
        const IntRegIndex rn = (IntRegIndex)(uint32_t)RN;
        const IntRegIndex rm = (IntRegIndex)(uint32_t)RM;
        const IntRegIndex rs = (IntRegIndex)(uint32_t)RS;
        switch (OPCODE) {
    '''
    decode_block += instCode(0x0, "and")
    decode_block += instCode(0x1, "eor")
    decode_block += instCode(0x2, "sub")
    decode_block += instCode(0x3, "rsb")
    decode_block += instCode(0x4, "add")
    decode_block += instCode(0x5, "adc")
    decode_block += instCode(0x6, "sbc")
    decode_block += instCode(0x7, "rsc")
    decode_block += instCode(0x8, "tst", dest="INTREG_ZERO")
    decode_block += instCode(0x9, "teq", dest="INTREG_ZERO")
    decode_block += instCode(0xa, "cmp", dest="INTREG_ZERO")
    decode_block += instCode(0xb, "cmn", dest="INTREG_ZERO")
    decode_block += instCode(0xc, "orr")
    decode_block += instCode(0xd, "mov", op1="INTREG_ZERO")
    decode_block += instCode(0xe, "bic")
    decode_block += instCode(0xf, "mvn", op1="INTREG_ZERO")
    decode_block += '''
          default:
            return new Unknown(machInst);
        }
    }
    '''
}};

def format ArmDataProcImm() {{
    instDecode = '''
          case %(opcode)#x:
            if (setCc) {
                return new %(className)sImmCc(machInst, %(dest)s, %(op1)s,
                                               imm, rotC);
            } else {
                return new %(className)sImm(machInst, %(dest)s, %(op1)s,
                                             imm, rotC);
            }
            break;
    '''

    def instCode(opcode, mnem, dest="rd", op1="rn"):
        global instDecode
        return instDecode % { "className": mnem.capitalize(),
                              "opcode": opcode,
                              "dest": dest,
                              "op1": op1 }

    decode_block = '''
    {
        const bool setCc = (bits(machInst, 20) == 1);
        const uint32_t unrotated = bits(machInst, 7, 0);
        const uint32_t rotation = (bits(machInst, 11, 8) << 1);
        const bool rotC = (rotation != 0);
        const uint32_t imm = rotate_imm(unrotated, rotation);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)RD;
        const IntRegIndex rn = (IntRegIndex)(uint32_t)RN;
        switch (OPCODE) {
    '''
    decode_block += instCode(0x0, "and")
    decode_block += instCode(0x1, "eor")
    decode_block += instCode(0x2, "sub")
    decode_block += instCode(0x3, "rsb")
    decode_block += instCode(0x4, "add")
    decode_block += instCode(0x5, "adc")
    decode_block += instCode(0x6, "sbc")
    decode_block += instCode(0x7, "rsc")
    decode_block += instCode(0x8, "tst", dest="INTREG_ZERO")
    decode_block += instCode(0x9, "teq", dest="INTREG_ZERO")
    decode_block += instCode(0xa, "cmp", dest="INTREG_ZERO")
    decode_block += instCode(0xb, "cmn", dest="INTREG_ZERO")
    decode_block += instCode(0xc, "orr")
    decode_block += instCode(0xd, "mov", op1="INTREG_ZERO")
    decode_block += instCode(0xe, "bic")
    decode_block += instCode(0xf, "mvn", op1="INTREG_ZERO")
    decode_block += '''
          default:
            return new Unknown(machInst);
        }
    }
    '''
}};

def format Thumb16ShiftAddSubMoveCmp() {{
    decode_block = '''
    {
        const uint32_t imm5 = bits(machInst, 10, 6);
        const uint32_t imm3 = bits(machInst, 8, 6);
        const uint32_t imm8 = bits(machInst, 7, 0);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 2, 0);
        const IntRegIndex rd8 = (IntRegIndex)(uint32_t)bits(machInst, 10, 8);
        const IntRegIndex rn = (IntRegIndex)(uint32_t)bits(machInst, 5, 3);
        const IntRegIndex rm = (IntRegIndex)(uint32_t)bits(machInst, 8, 6);
        switch (bits(machInst, 13, 11)) {
          case 0x0: // lsl
            return new MovReg(machInst, rd, INTREG_ZERO, rn, imm5, LSL);
          case 0x1: // lsr
            return new MovReg(machInst, rd, INTREG_ZERO, rn, imm5, LSR);
          case 0x2: // asr
            return new MovReg(machInst, rd, INTREG_ZERO, rn, imm5, ASR);
          case 0x3:
            switch (bits(machInst, 10, 9)) {
              case 0x0:
                return new AddReg(machInst, rd, rn, rm, 0, LSL);
              case 0x1:
                return new SubReg(machInst, rd, rn, rm, 0, LSL);
              case 0x2:
                return new AddImm(machInst, rd, rn, imm3, true);
              case 0x3:
                return new SubImm(machInst, rd, rn, imm3, true);
            }
          case 0x4:
            return new MovImm(machInst, rd8, INTREG_ZERO, imm8, true);
          case 0x5:
            return new CmpImmCc(machInst, INTREG_ZERO, rd8, imm8, true);
          case 0x6:
            return new AddImm(machInst, rd8, rd8, imm8, true);
          case 0x7:
            return new SubImm(machInst, rd8, rd8, imm8, true);
        }
    }
    '''
}};

def format Thumb16DataProcessing() {{
    decode_block = '''
    {
        const IntRegIndex rdn = (IntRegIndex)(uint32_t)bits(machInst, 2, 0);
        const IntRegIndex rm = (IntRegIndex)(uint32_t)bits(machInst, 5, 3);
        switch (bits(machInst, 9, 6)) {
          case 0x0:
            return new AndReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0x1:
            return new EorReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0x2: //lsl
            return new MovRegReg(machInst, rdn, INTREG_ZERO, rdn, rm, LSL);
          case 0x3: //lsr
            return new MovRegReg(machInst, rdn, INTREG_ZERO, rdn, rm, LSR);
          case 0x4: //asr
            return new MovRegReg(machInst, rdn, INTREG_ZERO, rdn, rm, ASR);
          case 0x5:
            return new AdcReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0x6:
            return new SbcReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0x7: // ror
            return new MovRegReg(machInst, rdn, INTREG_ZERO, rdn, rm, ROR);
          case 0x8:
            return new TstReg(machInst, INTREG_ZERO, rdn, rm, 0, LSL);
          case 0x9:
            return new RsbImm(machInst, rdn, rm, 0, true);
          case 0xa:
            return new CmpReg(machInst, INTREG_ZERO, rdn, rm, 0, LSL);
          case 0xb:
            return new CmnReg(machInst, INTREG_ZERO, rdn, rm, 0, LSL);
          case 0xc:
            return new OrrReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0xd:
            //XXX Implement me!
            return new WarnUnimplemented("mul", machInst);
          case 0xe:
            return new BicReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0xf:
            return new MvnReg(machInst, rdn, INTREG_ZERO, rm, 0, LSL);
        }
    }
    '''
}};

def format Thumb16SpecDataAndBx() {{
    decode_block = '''
    {
        const IntRegIndex rdn =
            (IntRegIndex)(uint32_t)(bits(machInst, 2, 0) |
                                    (bits(machInst, 7) << 3));
        const IntRegIndex rm = (IntRegIndex)(uint32_t)bits(machInst, 6, 3);
        switch (bits(machInst, 9, 8)) {
          case 0x0:
            return new AddReg(machInst, rdn, rdn, rm, 0, LSL);
          case 0x1:
            return new CmpReg(machInst, INTREG_ZERO, rdn, rm, 0, LSL);
          case 0x2:
            return new MovReg(machInst, rdn, INTREG_ZERO, rm, 0, LSL);
          case 0x3:
            if (bits(machInst, 7) == 0) {
                return new BxReg(machInst,
                                 (IntRegIndex)(uint32_t)bits(machInst, 6, 3),
                                 COND_UC);
            } else {
                return new BlxReg(machInst,
                                  (IntRegIndex)(uint32_t)bits(machInst, 6, 3),
                                  COND_UC);
            }
        }
    }
    '''
}};

def format Thumb16Adr() {{
    decode_block = '''
    {
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 10, 8);
        const uint32_t imm8 = bits(machInst, 7, 0) << 2;
        return new AddImm(machInst, rd, INTREG_PC, imm8, true);
    }
    '''
}};

def format Thumb16AddSp() {{
    decode_block = '''
    {
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 10, 8);
        const uint32_t imm8 = bits(machInst, 7, 0) << 2;
        return new AddImm(machInst, rd, INTREG_SP, imm8, true);
    }
    '''
}};

def format Thumb16Misc() {{
    decode_block = '''
    {
        switch (bits(machInst, 11, 8)) {
          case 0x0:
            if (bits(machInst, 7)) {
                return new SubImm(machInst, INTREG_SP, INTREG_SP,
                                   bits(machInst, 6, 0) << 2, true);
            } else {
                return new AddImm(machInst, INTREG_SP, INTREG_SP,
                                   bits(machInst, 6, 0) << 2, true);
            }
          case 0x1:
            return new Cbz(machInst,
                           (bits(machInst, 9) << 6) |
                           (bits(machInst, 7, 3) << 1),
                           (IntRegIndex)(uint32_t)bits(machInst, 2, 0));
          case 0x2:
            switch (bits(machInst, 7, 6)) {
              case 0x0:
                return new WarnUnimplemented("sxth", machInst);
              case 0x1:
                return new WarnUnimplemented("sxtb", machInst);
              case 0x2:
                return new WarnUnimplemented("uxth", machInst);
              case 0x3:
                return new WarnUnimplemented("uxtb", machInst);
            }
          case 0x3:
            return new Cbz(machInst,
                           (bits(machInst, 9) << 6) |
                           (bits(machInst, 7, 3) << 1),
                           (IntRegIndex)(uint32_t)bits(machInst, 2, 0));
          case 0x4:
          case 0x5:
            return new WarnUnimplemented("push", machInst);
          case 0x6:
            {
                const uint32_t opBits = bits(machInst, 7, 5);
                if (opBits == 2) {
                    return new WarnUnimplemented("setend", machInst);
                } else if (opBits == 3) {
                    return new WarnUnimplemented("cps", machInst);
                }
            }
          case 0x9:
            return new Cbnz(machInst,
                            (bits(machInst, 9) << 6) |
                            (bits(machInst, 7, 3) << 1),
                            (IntRegIndex)(uint32_t)bits(machInst, 2, 0));
          case 0xa:
            switch (bits(machInst, 7, 5)) {
              case 0x0:
                return new WarnUnimplemented("rev", machInst);
              case 0x1:
                return new WarnUnimplemented("rev16", machInst);
              case 0x3:
                return new WarnUnimplemented("revsh", machInst);
              default:
                break;
            }
            break;
          case 0xb:
            return new Cbnz(machInst,
                            (bits(machInst, 9) << 6) |
                            (bits(machInst, 7, 3) << 1),
                            (IntRegIndex)(uint32_t)bits(machInst, 2, 0));
          case 0xc:
          case 0xd:
            return new WarnUnimplemented("pop", machInst);
          case 0xe:
            return new WarnUnimplemented("bkpt", machInst);
          case 0xf:
            if (bits(machInst, 3, 0) != 0)
                return new WarnUnimplemented("it", machInst);
            switch (bits(machInst, 7, 4)) {
              case 0x0:
                return new WarnUnimplemented("nop", machInst);
              case 0x1:
                return new WarnUnimplemented("yield", machInst);
              case 0x2:
                return new WarnUnimplemented("wfe", machInst);
              case 0x3:
                return new WarnUnimplemented("wfi", machInst);
              case 0x4:
                return new WarnUnimplemented("sev", machInst);
              default:
                return new WarnUnimplemented("unallocated_hint", machInst);
            }
          default:
            break;
        }
        return new Unknown(machInst);
    }
    '''
}};

def format Thumb32DataProcModImm() {{

    def decInst(mnem, dest="rd", op1="rn"):
        return '''
            if (s) {
                return new %(mnem)sImmCc(machInst, %(dest)s,
                                          %(op1)s, imm, true);
            } else {
                return new %(mnem)sImm(machInst, %(dest)s,
                                        %(op1)s, imm, true);
            }
        ''' % {"mnem" : mnem, "dest" : dest, "op1" : op1}

    decode_block = '''
    {
        const uint32_t op = bits(machInst, 24, 21);
        const bool s = (bits(machInst, 20) == 1);
        const IntRegIndex rn = (IntRegIndex)(uint32_t)bits(machInst, 19, 16);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 11, 8);
        const uint32_t ctrlImm = bits(machInst.instBits, 26) << 3 |
                                 bits(machInst, 14, 12);
        const uint32_t dataImm = bits(machInst, 7, 0);
        const uint32_t imm = modified_imm(ctrlImm, dataImm);
        switch (op) {
          case 0x0:
            if (rd == INTREG_PC) {
                %(tst)s
            } else {
                %(and)s
            }
          case 0x1:
            %(bic)s
          case 0x2:
            if (rn == INTREG_PC) {
                %(mov)s
            } else {
                %(orr)s
            }
          case 0x3:
            if (rn == INTREG_PC) {
                %(mvn)s
            } else {
                %(orn)s
            }
          case 0x4:
            if (rd == INTREG_PC) {
                %(teq)s
            } else {
                %(eor)s
            }
          case 0x8:
            if (rd == INTREG_PC) {
                %(cmn)s
            } else {
                %(add)s
            }
          case 0xa:
            %(adc)s
          case 0xb:
            %(sbc)s
          case 0xd:
            if (rd == INTREG_PC) {
                %(cmp)s
            } else {
                %(sub)s
            }
          case 0xe:
            %(rsb)s
          default:
            return new Unknown(machInst);
        }
    }
    ''' % {
        "tst" : decInst("Tst", "INTREG_ZERO"),
        "and" : decInst("And"),
        "bic" : decInst("Bic"),
        "mov" : decInst("Mov", op1="INTREG_ZERO"),
        "orr" : decInst("Orr"),
        "mvn" : decInst("Mvn", op1="INTREG_ZERO"),
        "orn" : decInst("Orn"),
        "teq" : decInst("Teq", dest="INTREG_ZERO"),
        "eor" : decInst("Eor"),
        "cmn" : decInst("Cmn", dest="INTREG_ZERO"),
        "add" : decInst("Add"),
        "adc" : decInst("Adc"),
        "sbc" : decInst("Sbc"),
        "cmp" : decInst("Cmp", dest="INTREG_ZERO"),
        "sub" : decInst("Sub"),
        "rsb" : decInst("Rsb")
    }
}};

def format Thumb32DataProcPlainBin() {{
    decode_block = '''
    {
        const uint32_t op = bits(machInst, 24, 20);
        const IntRegIndex rn = (IntRegIndex)(uint32_t)bits(machInst, 19, 16);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 11, 8);
        switch (op) {
          case 0x0:
            {
                const uint32_t imm = bits(machInst, 7, 0) |
                                     (bits(machInst, 14, 12) << 8) |
                                     (bits(machInst, 26) << 11);
                return new AddImm(machInst, rd, rn, imm, true);
            }
          case 0x4:
            {
                const uint32_t imm = bits(machInst, 7, 0) |
                                     (bits(machInst, 14, 12) << 8) |
                                     (bits(machInst, 26) << 11) |
                                     (bits(machInst, 19, 16) << 12);
                return new MovImm(machInst, rd, INTREG_ZERO, imm, true);
            }
          case 0xa:
            {
                const uint32_t imm = bits(machInst, 7, 0) |
                                     (bits(machInst, 14, 12) << 8) |
                                     (bits(machInst, 26) << 11);
                return new SubImm(machInst, rd, rn, imm, true);
            }
          case 0xc:
            {
                const uint32_t imm = bits(machInst, 7, 0) |
                                     (bits(machInst, 14, 12) << 8) |
                                     (bits(machInst, 26) << 11) |
                                     (bits(machInst, 19, 16) << 12);
                return new MovtImm(machInst, rd, rd, imm, true);
            }
          case 0x12:
            if (!(bits(machInst, 14, 12) || bits(machInst, 7, 6))) {
                return new WarnUnimplemented("ssat16", machInst);
            }
            // Fall through on purpose...
          case 0x10:
            return new WarnUnimplemented("ssat", machInst);
          case 0x14:
            return new WarnUnimplemented("sbfx", machInst);
          case 0x16:
            if (rn == 0xf) {
                return new WarnUnimplemented("bfc", machInst);
            } else {
                return new WarnUnimplemented("bfi", machInst);
            }
          case 0x1a:
            if (!(bits(machInst, 14, 12) || bits(machInst, 7, 6))) {
                return new WarnUnimplemented("usat16", machInst);
            }
            // Fall through on purpose...
          case 0x18:
            return new WarnUnimplemented("usat", machInst);
          case 0x1c:
            return new WarnUnimplemented("ubfx", machInst);
          default:
            return new Unknown(machInst);
        }
    }
    '''
}};

def format Thumb32DataProcShiftReg() {{

    def decInst(mnem, dest="rd", op1="rn"):
        return '''
            if (s) {
                return new %(mnem)sRegCc(machInst, %(dest)s,
                                          %(op1)s, rm, amt, type);
            } else {
                return new %(mnem)sReg(machInst, %(dest)s,
                                        %(op1)s, rm, amt, type);
            }
        ''' % {"mnem" : mnem, "dest" : dest, "op1" : op1}

    decode_block = '''
    {
        const uint32_t op = bits(machInst, 24, 21);
        const bool s = (bits(machInst, 20) == 1);
        const IntRegIndex rn = (IntRegIndex)(uint32_t)bits(machInst, 19, 16);
        const IntRegIndex rd = (IntRegIndex)(uint32_t)bits(machInst, 11, 8);
        const IntRegIndex rm = (IntRegIndex)(uint32_t)bits(machInst, 3, 0);
        const uint32_t amt = (bits(machInst, 14, 12) << 2) |
                              bits(machInst, 7, 6);
        const ArmShiftType type = (ArmShiftType)(uint32_t)bits(machInst, 5, 4);
        switch (op) {
          case 0x0:
            if (rd == INTREG_PC) {
                %(tst)s
            } else {
                %(and)s
            }
          case 0x1:
            %(bic)s
          case 0x2:
            if (rn == INTREG_PC) {
                %(mov)s
            } else {
                %(orr)s
            }
          case 0x3:
            if (rn == INTREG_PC) {
                %(mvn)s
            } else {
                %(orn)s
            }
          case 0x4:
            if (rd == INTREG_PC) {
                %(teq)s
            } else {
                %(eor)s
            }
          case 0x6:
            return new WarnUnimplemented("pkh", machInst);
          case 0x8:
            if (rd == INTREG_PC) {
                %(cmn)s
            } else {
                %(add)s
            }
          case 0xa:
            %(adc)s
          case 0xb:
            %(sbc)s
          case 0xd:
            if (rd == INTREG_PC) {
                %(cmp)s
            } else {
                %(sub)s
            }
          case 0xe:
            %(rsb)s
          default:
            return new Unknown(machInst);
        }
    }
    ''' % {
        "tst" : decInst("Tst", "INTREG_ZERO"),
        "and" : decInst("And"),
        "bic" : decInst("Bic"),
        "mov" : decInst("Mov", op1="INTREG_ZERO"),
        "orr" : decInst("Orr"),
        "mvn" : decInst("Mvn", op1="INTREG_ZERO"),
        "orn" : decInst("Orn"),
        "teq" : decInst("Teq", "INTREG_ZERO"),
        "eor" : decInst("Eor"),
        "cmn" : decInst("Cmn", "INTREG_ZERO"),
        "add" : decInst("Add"),
        "adc" : decInst("Adc"),
        "sbc" : decInst("Sbc"),
        "cmp" : decInst("Cmp", "INTREG_ZERO"),
        "sub" : decInst("Sub"),
        "rsb" : decInst("Rsb")
    }
}};